Method Of Operation Of The 7Kn Powercenter 3000 Modbus Tcp Gateway - Siemens SENTRON 7KN POWERCENTER 3000 Manual

Functions
5.8 7KN POWERCENTER 3000 as a Modbus gateway
On a 7KN Powercenter 3000, identifiers can be assigned in the value range 1 to 247. The
number of devices actually supported on a 7KN Powercenter 3000 is shown in the technical
data. See Functional scope of 7KN POWERCENTER 3000 (Page 124).
The external identifiers are assigned automatically by powerconfig and stored in the
7KN Powercenter 3000 configuration. However, the external identifiers can also be
configured, e.g. if the configuration has to be adapted to an existing software program.
Powerconfig checks that the external identifiers are unique and requests that they are
corrected if necessary.
Note
Powerconfig automatically uses the addressing method described below to access the devices
on the smart assembly network. With powermanager, the IP address of the
7KN Powercenter 3000, communication via gateway must be activated, and the external
identifier entered as a unit address.
For addressing, the external identifier is put into the unit ID of the Modbus TCP protocol.
5.8.2

Method of operation of the 7KN POWERCENTER 3000 Modbus TCP Gateway

The Modbus TCP Gateway serializes all incoming access, irrespective of the particular
applications (= TCP connections).
It is then
• possible that multiple applications may access the connected devices in parallel, and
• applications that impact each other adversely, e.g. because of write access to the same
registers, must therefore be coordinated.
The performance is also restricted, in particular if the access is forwarded via a Modbus
TCP/RTU gateway (PAC4200).
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7KN POWERCENTER 3000
Equipment Manual, 07/2020, L1V30579222003-03